Jolt-actuated switch



Oct. 18, 1955 YUNKER JOLT-ACTUATED SWITCH Filed Aug. 50, 1952 EEUREEYL/NKER INVENTOR.

JOLT-ACTUATED SWITCH George Yunker, Portland, Greg. Application August3th, 1952, Serial No. Sit-7,345 1 Claim. (Cl. Zed-61.49)

This invention relates to improvements in automatic electric switchesespecially adapted for use with the electrical systems of engine drivenvehicles.

One of the principal objects of the invention is to provide a switch ofthis character which will automatically open the electrical circuitwithin which it is embraced upon being jolted by a collision or uponlateral impact from any direction.

Another object is the provision of means for quickly and convenientlyresetting the switch into a circuit-closing position and for adjustingthe sensitivity of the switch.

A still further object is the provision of a switch of this kind whichis of simple, efiicient, durable and inexpensive construction which maybe conveniently attached to a vehicle at any desired location andwherein its several parts are readily accessible for replacement,adjustment or repair.

These and other objects will appear as my invention is more fullyhereinafter described in the following specification, illustrated in theaccompanying drawing and finally pointed out in the appended claim.

In the drawing:

Figure 1 is a front view of a jolt-actuated switch made in accordancewith my invention and with fragments broken away for convenience ofillustration.

Figure 2 is a sectional plan view taken along the line 22 of Figure 1with the spring-pressed contact ball removed.

Figure 3 is a view similar to Figure l modified form of the invention.

Figure 4 is a sectional plan view taken along the line 44 of Figure 3with the contact ball removed.

Figure 5 is a detail view of an air and watertight hood and base.

Referring now more particularly to the drawing:

With reference to Figures 1 and 2, the invention comprises a circularbase 1 made of electrical insulating material and centrally bored as at2 to receive a cylinder split in half throughout its length to form twoelectrical contacts 3 and 4. Each contact is insulated from the other bybeing embedded in the insulating material of the base. The top edge ofeach contact 3 and 4 is bevelled inwardly as at 5 to form a seat for ametal contact ball 6. The top surface of the base 1 is formed with anannular recess 6A whose inner surface tapers downwardly from the seat 5on the top edges of the contacts 3 and 4 to offer a minimum ofresistance to the dislodgement of the ball from its seat and its passageto the recess when unseated by a jolt caused by collision or any otherimpact in a lateral direction. The ball is normally maintained on theseat by a light compression spring 7 whose one end is secured to theball by soldering, or the like, and whose upper end is secured in likemanner to the interior of a hollow and externally threaded adjustingscrew 8 whose top end is knurled as at 9 to provide a showing a nitedStates Patent Ofiice 2,721,237 Patented Get. 18, 1955 finger grip foradvancing and retracting the screw in relation to a metallic frame 10 inwhich the screw is threadedly mounted to increase or decrease thecompression of the spring 7. The legs of the frame are secured to thebase 1 by any suitable means, such as screws or the like, indicated at11. If it is desired to render the switch air and watertight, aninternally threaded hood 12 as shown in Figure 5 could be used byforming matching threads 12A on the exterior of the base 1.

The base is bored diametrically as at 13 to receive two wires 14 and 15of the electrical ignition system of the vehicle to which the switch isapplied. The wires are attached to the contacts 3 and 4 as shown so thatas long as the ball 6 remains on the seat 5, the electrical circuit willbe closed between the wires 14 and 15.

This form of the invention illustrated in Figures 1 and 2 is designed tohandle relatively high voltages, while the modified form illustrated inFigures 3 and 4 is designed for low voltage. In this modification, thestructure of the base, the frame, the contact ball, the spring and itsadjusting screw is the same as that shown in the other form of theinvention, but instead of providing two separate contacts 3 and 4 fortwo wires of the electrical circuit to be closed by the ball whenseated, I provide a single contact in the form of a cylinder 16 bevelledat its top end to form a seat for the ball 6B and connected by a wire 17to one side of the electrical circuit, whose other side is connected bywire 18 to the frame 10A. The ball is in electrical contact with theframe through the compression spring 7A and the circuit between thewires 17 and 18 will therefore remain closed as long as the ball remainson the seat on the top of the cylindrical contact 16.

While I have shown particular forms of embodiment of my invention, I amaware that many minor changes therein will readily suggest themselves toothers skilled in the art without departing from the spirit and scope ofthe invention. Having thus described my invention, what I claim as newand desire to protect by Letters Patent is:

A switch of the character described comprising in combination ahorizontally disposed circular base made of insulating material, anelectrical contact in the form of a vertically disposed hollow metalliccylinder mounted centrally of the base and forming a circular seat atits top end, a metallic ball normally resting upon said seat, the topsurface of the base having an annular recess formed therein below saidseat and concentric therewith, a vertically disposed metallic frameremovably secured to said base, a compression spring adjustablyconnected at one of its ends to the top of said frame and permanentlysecured at its opposite end to said ball for normally maintaining theball on the seat under variable degrees of pressure, said frame beingconnected to one side of an electrical circuit and said cylinder beingconnected to the other side thereof whereby said circuit will be brokenwhen the ball is dislodged from said circular seat by forces applied toit from any lateral direction and forced into and held within saidannular recess in the insulated base by said compression spring.

References Cited in the file of this patent UNITED STATES PATENTS1,901,554 De Wilde Mar. 14, 1933 2,056,494 Tucker et al. Oct. 6, 19362,475,728 Smith July 12, 1949 FOREIGN PATENTS 287,780 Great Britain Mar.29, 1928

